Gauge for swaging tool



Dec. 1, 1959 F. R. WILSON GAUGE FOR SWAGING TQOL Filed Jan. 9. 1956 INVENTOR. FRAN K R. WILSON BY DES JARDINS, ROBINSON 8. KEISER HIS ATTOR NEYS iew-w mined: i s. atent 2,915,107 GAUGE FOR SWAGING TOOL Frank R. Wilson, Memphis, Tenn., assign'or to Quinn Esther Wilson This invention relates to a swaging tool for expanding the end of a piece of tubing and, more particularly, to a gauge for measuring off the length of tubing to be expanded by the tool so as to enable the proper-length of tubing to be inserted into the vise or clamping die prepara tory to being swaged. V

The customary procedure followed in swaging the end of a piece of tubing by a manually operable tool is to insert the end of the tubing in a clamping die with the end of the tubing which is to be expanded projecting above the die. The pilot on the swaging tool is then inserted in the end of the tubing and the sizing anvil of the tool is then forced down into the end of the tubing to expand it to the proper dimension. In performing this operation it is desirable that only so much of the tubing be permitted to remain extending above the clamping die as is necessary toform the expanded portion thereon. If

the piece of tubing extending beyond the clamping die is longer than the length'of the expanded portion to be formed thereon, the forcing of the swaging tool into the end of the tubing is likely to deform the unsupported length of tubing extending beyond the clamping die. On the other hand, if the length of tubing left projecting above the clamping die is shorter than the length of the portion of the tubing to be expanded by the tool, there is always the danger that the swaging tool may be driven into the clamping die and thereby weaken the tubing at the bottom of the expanded portion. Even if the operator is sufficiently careful to prevent this from happening, he must nevertheless release the tubing in the clamping die and move an additional length of tubing out of the die to permit the completion of the swaging operation.

In the past, the matter ofdetermining the proper length of tubing to be inserted into the clamping die preparatory to a swaging operation was left to the skill and experience of the user of the tool who would be required to visually estimate whether or not the amount of tubing projecting above the clamping die was equal to, or only slightly greater than, the length of tubing to be expanded by the tool. For persons lacking the necessary experience and expertness for thus judging the distance to which the tub ing should extend from the clamping die, an inferior swaging job would be likely to result. This would not come to pass through any fault of the tool but simply because of the inability of an inexperienced user to correctly judge the length of tubing necessary for the operation.

In order to avoid this difiiculty and to guarantee that the correct amount of tubing will be left projecting above the clamping die, I have devised a means on the tool it self for gauging the position of the tubing within the clamping die so that when the latter is closed upon the tubing, the proper length of tubing will be extended from the die.

Accordingly, it is an object of the present invention to provide, on a tube swaging tool, a gauge for determining the extent to which the tubing should project above the clamping die in order to permit expansion of a pre- 2,915,107 Patented Dec. 1, 9

, "Z determine'd'length of the tubing without. producing any deformation thereof. A

Another object of the present invention isto provide a hand swaging tool for -expanding the'ends of tubing, said tool having gauging indicia located a predetermined distance in from one end thereof for use in determining the extent 'to which the tubing to be swaged should be extended above the clamping die for the performance of a satisfactory swaging-operation. e v With these and other objects in view which will become apparent from the following description, the inven tion includes certain novel features of construction and arrangements of parts, the essential elements of which are set forth in the appended, claims and a preferred form or embodiment of which will hereinafter be described with reference'to the drawings which accompany and form a part of this specification. 'In' the drawings: t Fig. l is a side elevation showing the invention as ap-' plied to a tube swaging tool of the hand operated type. Fig. 2 is a side elevation, partially in cross-section, showing the position the swaging tool occupies after it has been-forced into the end of the tubing to expand the same.

Fig. 3 is a cross-sectional view taken through a piece of tubing which has been expanded by the swaging tool as shown in the preceding figure.

In the present drawings :1 have shown my invention as applied to a hand swaging tool of the type which is adapted to be hammered into the end of a piece of tubing held in place in a vise or clampingdie. It is to be understood, of course,that theinvention mightb'e applied with equal facility to .otherforms of swaging'tools such as those in which the' swaging tool is forced into "the tubing by 'a feed screw operated by the user of thetotjll In any case, the tubing ,must be .held' fast v in -some term of tube clampingmeans during theperformanceof the swaging operation. As shown inFigs. 1 and 2, the tubing "10,'the end of which is to be enlarged by theswag ing tool, is held between the clamping blocks orb'ars 11 and 12 which are provided with matching semicylindrical recesses of varyingsizes to accommodate the difierent diameters of tubing norm ally required to be handle d by the tool.-- When the barsll and 12 are brought together, the matching semicylindrical recesses form cylindrical clamping apertures which are normally designedto be ofislightly smaller diameter than the outside jdiameterof the tubing. These apertures are indicated in the present drawings by reference numeral 13 and they are ordinarily provided withgserrations 14, for preventing slippage of the tubing therein under the pressures exerted axially thereon'during the forming operation. The apertures 13 are also'usually provided with vchamfcrs .15 at their upper ends to form a backup surface of the outer wall' of the tubing when the same is flared out by a cone-shaped flaring tool. In Figs. '1 and 2, the tubing 10 'is'shown inserted in'one of the clamping apertures 13 and it will be" understood that it is intended-"to, be held securely therein by' suitable clamping means provided for draw: ing thebar's 11 and 12 firmly together on the tube to hold it in position as shown. This clamping means may take any of the forms which are well known to the art. The hand swaging tool shown in the present drawings includes a hexagonal handle portion 20 by which the tool is grasped and manipulated by the user thereof. At the lower end of the handle, the tool is provided with a shoulder 21 which serves as a stop for engaging the upper end of the tubing 10 and limiting the insertion of the swaging tool into the tubing as shown in Fig. 2. Below the shoulder, the tool is provided with a sizing anvil 22 which is connected by a taper 23 with a pilot 24, which also serves as a gauge means for determining the correct length of tubing to be left extending above the clamping die. The diameter of the pilot portion 24 is such as to provide a snug, sliding fit thereof inside the tubing prior to anyexpansion of the tubing by the tool. The anvil 22 is of such diameter as to expand the tubing to the desired inside diameter when the tool is forced therein as shown in Fig. 2.

The novel feature of the swaging tool herein disclosed resides in combining the gauge means with the pilot so as to provide means for enabling the user of thetool to make a quick andaccurate determination of the length of tubing which should be left extending beyond the clamping die when the tubing is clamped therein preparatory to the performance of a swaging operation. In the embodiment of theinvention hereindisclosed, .the gauge means includes a ring or groove26 extending around the pilot portion 24, and a gauging surface27 formed on the end of the portion 24. The distance'betweenthe indicia 26 and the surface 27is such as to provide the correct amount of tubing extending above thedie .for the formation of the expanded portion 25 thereon. As shown in Fig. 2, this distance should be such asfto cause the upper end 28 (Fig. 1) of the tubing 10 to strike the shoulder 21 and prevent further entrance of the swaging tool into the tubing a measurable distance before the bottom of the taper 23 reaches the upper end 29 (Fig. 2) of the clamping aperture 13. tubing by the forcing of the wall thereof against the sharp corner 29 by the taper 23 on the tool will be pre vented. As shown in'Fig. 2, the measurable distance above referred to, is the distance between the root 30 of the expanded portion 25 of the tubing and the upper end of the clamping aperture 29. This distance should be kept small so as to reduce to a minimum the amount of unsupported tubing lying above the upper end 29 of the clamping aperture while providing a sufficient margin of safety to'prevent any possibility of indenting of the tubing by the sharp corner existing at 29. The gauging distance between the surface 27 and the indicia 26 is substantially equal to the length of the sizing anvil 22 although, of course, the presence or absence of a chamfer on the clamping aperture will affect this distance since the surface '27 rests on the upper surface of the clamping die whether or not a chamfer is provided. The groove 26 is preferably filled with paint having a color that contrasts with that of the material from which the tool is formed'so as to provide a readily distinguishable and permanent type of gauging indicia on the pilot of the tool.

The operation of my new gauging device is .asfollows:

'The tubing to be expanded is inserted in the clamping die with the end 28 thereof projecting above the top surface of the die as shown in Fig. 1. The extent to which the end of the tubing is projected above the die is determined by placing the surface 27 on the bottom of the pilot 24 on top of the clamping die adjacent the tubing and thereafter adjusting the tubing up and down within the clamping aperture until the end 28 thereof lies directly opposite the indicia 26 inscribed on the tool. The clamping die is then tightened on the tubing after which the pilot 24 is inserted in the end of the tubing and the sizing anvil 22 driven into the tubing to expand the upper end of the same. After the shoulder 21 comes In this way, indentation of the into contact with the upper end 28 of the tubing, the tool will occupy the position shown in Fig. 2 and expansion of the tubing will have been completed. The tool is thereupon withdrawn from the tubing and the latter is removed from the clamping die. The finished form of the tubing is shown in Fig. 3. By thus gauging the length of tubing extending above the clamping die prior to the swaging operation, exactly the right amount of tubing will be provided above the die for the formation of the expanded portion 25 thereon and a dimensionally accurate piece of tubing will be produced.

While I have described my invention in connection withone possible form or embodiment thereof and have used, therefore, certain specific terms and language herein, it is to be understood that the present disclosure is illustrative rather than restrictive and that changes and modifications may be resorted to Without departing from the spirit or the scope of the claims whichfollow.

Having thus described ,my'invention, what I claim as new and useful, and desire to secure by United States Letters Patent is:

1. A swaging tool of the type adapted to be forced into the end of a piece of tubing held in place in a clamping die comprising gauging means including a gauging surface on one end of said tool, indicia located on the side of said tool and spaced from said one end a predetermined distance, said tool including a pilot adapted to enter the end of said tubing and guide the tool therein, a sizing anvil lying immediately beyond said pilot for expanding the tubing as the tool is forced therein, a stop shoulder provided at the upper end of said anvil for limiting the insertion of the anvil into the endof the tubing, and wherein said predetermined distance is substantially equal to the length of said anvil.

2. A swaging tool of the type adapted to be forced into the end of a piece of tubing held in place in a clamping die comprising gauging means including a gauging surface on one end of said tool, indicia located on the side of said tool and spaced from said one end a predetermined distance, said tool including a pilot adapted to enter the end of said tubing and guide the tool therein, a sizing anvil lying immediately beyond said pilot for expanding the tubing as the tool is forced therein, a stop shoulder provided at the upper end of said anvil for limiting the insertion of the anvil into the end of the tubing, said predetermined distance being substantially equal to the length of said anvil, said indicia comprising a circumferential groove formed in said pilot, and said pilot being longer than said anvil portion.

References Cited in the file of this patent UNITED STATES PATENTS 1,560,186 Muth Nov. 3, 1925 1,996,346 Mueller Apr. 2, 1935 2,278,932 Kellems Apr. 7, 1942 2,476,480 Burekle July 19, 1949 2,493,127 Frank Jan. 3, 1950 2,517,345 Pies Aug. 1, 1950 2,797,726 Granville July 2, 1957 FOREIGN PATENTS 1,100,631 France Apr. 6, 1955 

